The role that biophysical forces play in regenerative medicine is expanding, with increased interest in the use of intrinsic electrical forces (via regulation of cell membrane channels) and externally applied electric fields (via bioreactor environments) as important control points. Despite significant potential of electrical signals for regenerative medicine, they have not yet been integrated into the design of tissue engineering systems. We propose a radically new strategy to improve connective tissue regeneration by electrotherapeutic control of cell function, through the integrated use of molecular and electrical control of cell function and tissue formation. Our hypothesis is that the synergistic application of molecular control of transmembrane ion flux and externally applied electric fields will improve the quality of cartilage and bone regeneration and accelerate their integration in vivo. We will rigorously test this hypothesis by studying the regeneration of composite bone/cartilage grafts. The regulation of cell function and tissue regeneration will be first studied in vitro using controlled bioreactor environments, and then in vivo in an orthotropic animal model of cartilage and bone regeneration. Three specific aims will be pursued: (a) Biophysical regulation of chondrogenesis and osteogenesis in adult human stem cells, (b) Electrotherapeutic bioreactor models for regeneration of cartilage/bone tissues, and (c) Animal studies of cartilage/bone regeneration. The anticipated scientific impact will be in significant new insights into the biophysical control of connective tissue repair by modulation of electrical regulatory signals. The main technological impact will be in improved regeneration of cartilage/bone tissues, and the new generation of electrotherapeutic medical devices termed BioDomes.